:root {
  --bg: #fbfaf7;
  --surface: #ffffff;
  --text: #1f2328;
  --muted: #5d6670;
  --border: #e3e0d8;
  --accent: #306998;        /* Python blue */
  --accent-2: #f2c230;      /* Python yellow, slightly deepened */
  --done-bg: #306998;
  --done-text: #ffffff;
  --cell-bg: #efece5;
  --cell-text: #9a9488;
  --code-bg: #f5f3ee;
  --radius: 10px;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", Inter, Roboto, sans-serif;
  --mono: ui-monospace, "SF Mono", Menlo, Consolas, monospace;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #14171b;
    --surface: #1b1f24;
    --text: #e6e3dc;
    --muted: #9aa3ad;
    --border: #2c3138;
    --accent: #7fb2e0;
    --accent-2: #ffd43b;
    --done-bg: #4b8bc4;
    --done-text: #0f1215;
    --cell-bg: #22272d;
    --cell-text: #5a626b;
    --code-bg: #0d1117;
  }
}

* { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 17px/1.65 var(--font);
}

a { color: var(--accent); text-underline-offset: 2px; }

.wrap { max-width: 46rem; margin: 0 auto; padding: 0 16px; }

/* Header / footer */
.site-header { border-bottom: 1px solid var(--border); background: var(--surface); }
.site-header .wrap { display: flex; align-items: center; justify-content: space-between; gap: 1rem; min-height: 3.5rem; flex-wrap: wrap; }
.brand { display: flex; align-items: center; gap: .55rem; font-weight: 700; color: var(--text); text-decoration: none; }
.brand-mark { background: var(--accent); color: var(--accent-2); border-radius: 6px; padding: 0 .4rem; font-size: .85rem; line-height: 1.6; }
@media (prefers-color-scheme: dark) { .brand-mark { background: #306998; } }
nav { display: flex; gap: 1.1rem; }
nav a { color: var(--muted); text-decoration: none; font-size: .95rem; }
nav a:hover { color: var(--text); }

.site-footer { margin-top: 4rem; padding: 2rem 0 3rem; border-top: 1px solid var(--border); color: var(--muted); font-size: .85rem; }
.site-footer a { color: inherit; }

/* Home */
.hero { padding: 2.5rem 0 1.5rem; }
.hero h1 { font-size: 2.1rem; line-height: 1.2; margin: 0 0 .4rem; letter-spacing: -.01em; }
.lede { color: var(--muted); margin: 0 0 1.75rem; }

.progress { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 1rem; }
.progress-count { margin-bottom: .75rem; color: var(--muted); }
.progress-count strong { color: var(--text); font-size: 1.4rem; }

.grid { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(20, 1fr); gap: 4px; }
.grid li { aspect-ratio: 1; display: grid; place-items: center; border-radius: 4px; background: var(--cell-bg); color: var(--cell-text); font-size: .6rem; font-variant-numeric: tabular-nums; }
.grid li.done { background: var(--done-bg); }
.grid li.done a { color: var(--done-text); text-decoration: none; width: 100%; height: 100%; display: grid; place-items: center; font-weight: 600; }
@media (max-width: 560px) {
  .grid { grid-template-columns: repeat(10, 1fr); }
  .grid li { font-size: .7rem; }
}

.log { margin-top: 2rem; }
.entry { padding: 1.4rem 0; border-bottom: 1px solid var(--border); }
.entry h2 { font-size: 1.3rem; line-height: 1.3; margin: .35rem 0 .3rem; }
.entry h2 a { color: var(--text); text-decoration: none; }
.entry h2 a:hover { color: var(--accent); }
.entry p { margin: 0; color: var(--muted); }

.entry-meta { display: flex; flex-wrap: wrap; align-items: center; gap: .3rem .75rem; font-size: .85rem; color: var(--muted); }
.day-badge { background: var(--accent-2); color: #1f2328; font-weight: 700; border-radius: 999px; padding: .05rem .6rem; font-size: .78rem; }
.topic::before { content: "· "; }
.draft { border: 1px dashed currentColor; border-radius: 4px; padding: 0 .4rem; }

/* Post */
.post { padding-top: 2.5rem; }
.post h1 { font-size: 2rem; line-height: 1.2; margin: .5rem 0 .4rem; letter-spacing: -.01em; }
.module { color: var(--muted); font-size: .95rem; margin: 0 0 2rem; }

.prose h2 { font-size: 1.35rem; margin: 2.2rem 0 .6rem; }
.prose h3 { font-size: 1.1rem; margin: 1.8rem 0 .5rem; }
.prose img { max-width: 100%; height: auto; border-radius: var(--radius); }
.prose blockquote { margin: 1.2rem 0; padding: .2rem 1rem; border-left: 3px solid var(--accent-2); color: var(--muted); }
.prose table { border-collapse: collapse; width: 100%; display: block; overflow-x: auto; font-size: .95rem; }
.prose th, .prose td { border: 1px solid var(--border); padding: .4rem .6rem; text-align: left; }

code { font-family: var(--mono); font-size: .88em; background: var(--code-bg); padding: .1em .35em; border-radius: 4px; }
.highlight { background: var(--code-bg) !important; border: 1px solid var(--border); border-radius: var(--radius); overflow-x: auto; margin: 1.2rem 0; }
.highlight pre { margin: 0; padding: .9rem 1rem; font-size: .85rem; line-height: 1.55; }
.highlight code { background: none; padding: 0; font-size: inherit; }

.tags { list-style: none; padding: 0; margin: 2.5rem 0 0; display: flex; flex-wrap: wrap; gap: .4rem; }
.tags li { font-size: .8rem; color: var(--muted); border: 1px solid var(--border); border-radius: 999px; padding: .1rem .65rem; }

.pager { display: flex; justify-content: space-between; gap: 1rem; margin-top: 3rem; padding-top: 1.5rem; border-top: 1px solid var(--border); font-size: .92rem; }
.pager a { text-decoration: none; max-width: 48%; }
.pager .newer { text-align: right; margin-left: auto; }